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Full text of "Tests with DDT nonionic emulsion for mothproofing washable woolens"

LIBRARY 

p ^M OARD 



E-858 



United States Department of Agriculture 

Agricultural Research Administration 

Bureau of Entomology and Plant Quarantine 



TESTS WITH DDT NONIONIC EMULSION FOR 
MOTHPROOFING WASHABLE WOOLENS 

By Hamilton Laudani-i/ 
Division of Stored Product Insect Investigations 



During an extensive investigation at the Savannah, Ga., laboratory 
of the possibilities of using DDT on woolens to prevent attack by fabric 
insects, it was noted that after woolen cloth was treated in a nonionic 
emulsion it contained a greater amount of DDT than could be accounted 
for by the proportional amount of DDT in the emulsion sorbed by the 
cloth. 

According to Goodall et al. (1946), DDT has no affinity for textiles 
because it has no salt-forming groups. Hall et al. (1949) and Jones et al. 
(1945) reported no selectivity when 50-percent- wool underwear was 
treated with 2-percent DDT nonionic emulsions. Moncrieff (1950) found 
that, although DDT normally does not have an affinity for wool, exhaustion 
took place when cationic emulsions were used under slightly acid condi- 
tions. It was his opinion that the substantivity probably had been gained 
by the use of the cationic surface-active agent. 

Studies on the selective pickup of DDT by woolens washed or soaked 
in very dilute nonionic emulsions of DDT are reported herein. 

Laboratory Tests 

Procedure 

Four series of laboratory tests were made with small patches of 
woolen cloth. In each of three series one factor was varied, and in the 
fourth series two factors were varied, as follows: 



1/ The assistance is acknowledged of C. Cueto, Wm. E. Dale, and 
D. E. Rabey in making the chemical analyses, and of F. O. Marzke, 
W. J. Patterson, and L. L. McDonald in making the biological tests. 






Series 

1 

Weight of ■ ount 

of DD1 

lume of emulsion bath, 
con n of DDT, and 

amount of DDT 
4 Volume of emulsion bath 



Va: . : ■ Y . •■ 

Amount I :ng 

vol on 

< ncentration of DDT (1 
increasing volun. 

»th 



Amount and concentration 
of DDT 
ght of cloth 

Th' LA official test cloth. Botany-style No. 315 broadcloth 100- 

percent wood.-a was used in all tests. h was washed for 10 

minutes in a home-type washing machine containing 10 tablespoonfuls of 
commercial soap flakes in 10 gallons of water, and then rinsed for 5 
minutes in 10 gallons of clea: Imm» I -ing and 

.ging, the cloth was agitated for 5 minutes in a DDT-i mulsion bath, 
again run through the wringer, and air-dried. The emulsifiable concen- 
te was composed of 30 percent of DDT, 60 p< md 10 

cent of Triton X-100. I tie ten perature of the water in all operations 
was 90° I 

: deposit of DDT in the cloth v. d on tl 

m of woolen cloth would absorb 1.4 ins of emulsion 

during the treatment. I tual amount if DDT on tl loth * 

lined by quantitative ai o < 

thod.<3f 

• 

The resul - table 1. 

i] ) n the cloth was m 
int. I: the bath containii . 
of the weight of tl .. 
ount. 



Sp< '■ ' Lion, 

Association of Official Agricult 
., p. 81, 18 



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In series 1, where the amount of available 1)1)1 irai i, the 

josit in the cloth increased ling 

In sc . where the entratii DD1 •'■■■- varied but the 

amount r< .oth r> 

les 3, whcic the weight of cloth was varied but the amount of 

T remained constant, the deposit in the cloth remained con 
In sei '■ , whe. .ount as increased, the depo:- 

in the cloth increased, even though the amount of cloth was n >d 

proportionate! . 

1 hese preliminary results indicated that (1) woolen cloth immersed 
in low concentrations of a nonionic emulsion of DDT ; up more 

DDT than was expected from absorption of the emulsion in the c loth, 
and (2) it was possible to control the amount of DDT deposited in 
cloth when using dilute emulsions. 

With greater insecticide de{x>sits than normally expected, the use 
of DDT emulsions of low concentrations for mothproofing washable 
woolens appeared to be pra< onomical. The use of such a 

treatment during the normal washing process looked very feasib . 

hods of application and dosages required for their use in con al 

laundries, home-type washing machines, and hand washing were the 
fore investigated. 

Tests in lmercia! I . 

Treatments were made u e laundry to d» :ie 

whether seb pickup of DDT would o< hen woolen blaj 

treated in standard commercial Laundry rinses am; amount of DDT 

nonioni< emulsifial U mcentrate ... S it 

appro* 

Procedui 

The blanket tied for 5 minutes in 4 

^ of d< >175). : • 

i- '., nd the wash. 
• ■ • - . .• ■ . • • • i ' • ■ 

he blank- • minuti 

• ■ i • ■ • . i 

le concenl rate v 

in thr 
min M 1 ,000 r.p.m. I then d 

I minui , g which I 

. . 

1 1). h\ foll< 



-5- 



Five series of tests were made in which 5 or 10 blankets were im- 
mersed in 0. 14-, 0. 24-, and 1.00-percent emulsions. The emulsifiable 
concentrate used in the first four series contained 30 percent of DDT, 
10 percent of Triton X-100,and 60 percent of xylene by weight. Of this 
concentrate, 769 ml. was used to make the 0.14-percent emulsion and 
5,351 ml. for the 1.00-percent emulsion. In the fifth series the emulsi- 
fiable concentrate contained 25 percent of DDT, 10 percent of Triton 
X-100, and 65 percent of Solvesso 100. To make the 0.24-percent 
emulsion, 1,466 ml. of concentrate was used to treat 10 blankets con- 
taining 40 pounds of wool. This gave 9,07 grams of DDT in the emulsion 
for each pound of wool. 

Samples cut from the corner and center of each blanket were analyzed 
to determine the DDT deposits. 

Results 

The deposits of DDT found in the blankets are given in table 2. In 
table 3 additional data relative to the series are given. 

These tests demonstrated that (1) selective pickup of DDT occurred 
under commercial laundry conditions with a considerable quantity of 
woolen material present, (2) the amount of pickup depended on the amount 
of DDT available in the rinse and the weight of woolens immersed, and 
(3) approximately 9 grams of DDT per pound of wool gave approximately 
0.5-percent deposit of DDT in the blankets. 

The first point is found by comparing the 3xpected deposit with the 
actual deposit in table 3. 

The second point can be demonstrated by cross comparison of the 
series. A comparison of the results obtained in series 1 and 3 or 2 
and 4, where the same amount of DDT was available in the rinse but 
the percent of DDT deposit was less in the 10-blanket lot than in the 
5 -blanket, shows a definite influence from the increased weight of 
blankets. By comparing the results obtained in series 1 and 2, or 3 and 
4, where the weight of the blankets was constant, the percent of DDT 
deposit was greater where the amount of DDT was greater, showing 
that the amount of DDT definitely influenced the DDT deposit in the 
blankets. 

In series 5 an amount of emulsifiable concentrate was added to give 
a theoretical deposit of 0.5 percent of DDT in the blankets as calculated 
from the results of the previous series. An actual deposit of 0.54 per- 
cent was obtained. 

These data are not extensive enough to determine the effect on the 
DDT deposit of the relation between the amount of DDT available and 
the weight of cloth immersed. In series 1 and 3 approximately 20 per- 
cent of the available DDT was taken up by the blankets. However, in 
series 2 and 4 no such consistency was obtained, the pickup being 5.9 
and 14.8 percent. However, the proportion of pickup increased as the 
ratio of weight of cloth to amount of DDT decreased. 






-DDT ' :ng treatment in a 

• ndry machj 



les 



Concenti 
tion of DDI 



; 
N . 



DO nt) 



I 



Cei 



ge 



5 blankets 

1 



Per 



0.14 



1.0 



10 blank, is 
3 



0.14 



1.0 



■ 



6 


0.32 


7 




8 


.79 


9 




10 


.36 


Average 


.46 


1 


1.03 


2 


1.65 


3 




4 


1.22 


5 


1.57 


Average 


1.30 


21 


0.23 


22 


.27 


23 


.48 


24 


. 


Average 


. _ 


11 


1.52 


12 


1.12 


13 


1.0 7 




. 




. 




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A 





.80 
. 

.81 
.60 

0.11 

. 
1.05 

. 
1.39 
0.96 



0.21 
.34 
. • 
.30 

. 
.31 

. 



0.39 
.39 
.80 

. 

1.31 

. 

. 



. 

,31 

.37 

. 



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wash • 1- 

washed for 

until 

if water to woo: shing to 1. 

5 had sho & 

the same whether tl 
dded during the washing or in the first nns- 

ite was : d simultaneously with the SO . 

:it cor- ition was us 

was used in the automatic and a 3 -cent 

Digitized by.the Internet Arcfiive 

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sits of DD 

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-9 - 

The average deposit of DDT in the blankets treated in the automatic 
washer was 0.43 percent, and in those treated in the nonautomatic was 
0.31. The difference may have been due in part to the difference in 
rinsing action. In any event, both deposits are sufficient to insure com- 
plete protection against fabric -insect damage, as will be shown later 
(page 12). 

These tests demonstrated that 1 tablespoonful of either 25- or 30- 
percent emulsifiable concentrate per pound of dry woolens, added to the 
wash water, gave an adequate deposit of DDT in the woolens in both 
automatic and nonautomatic home-type washing machines. 

Tests with DDT Concentrate in Combination with 
Detergents, Soap, or Soap with a Water Softener 

Another series of blanket treatments was made in home-type auto- 
matic washing machines in which two anionic detergents, a nonionic 
detergent, a soap, and soap in combination with a water softener were 
used in the washes. 

Procedure 

In these treatments 3 l/2 tablespoonfuls (52,5 ml.) of 30 -percent DDT 
nonionic emulsifiable concentrate was added to the wash water for each 
blanket. This is the equivalent to 1 tablespoonful per pound of dry wool. 
Detergents and soap were used at 0.2-percent concentration, and the 
softener at the rate of 1 teaspoonful per gallon of water. The washing 
and rinsing procedure was identical to that previously described for 
home-type washing machines. Duplicate treatments were made in two 
machines of the same make. 

Results 

As shown in table 5, the average amount of DDT picked up by the 
blankets was practically the same with all cleansing agents used. In 
treatment 6, where the insecticide was added in the first rinse in 
washer A and in the last rinse in washer B, the amount of DDT present 
was identical to that in treatment 1, in which the insecticide was added 
to the wash water. 



STATE PLANT BOARD 



10 - 



Dep< ol DD1 in I ited with DD'I emulsifiable 

imbination with detergents, soap, and soap plus a 
water soft*-.- 



Treatment 



Cleansing a/. 



DDT in blan) ^ht) 



Was' Washer B A 



1 Anionic detergent (Fab) 

2 Anionic detergent (Vel) 

3 Nonionic detergent (All) 

4 Soap (Lux) 

5 Soap plus softener (Lux 

plus Calgon) 

6 Anionic detergent (Fab) 



Per< >-nt 


PCI »*nt 


Pi 


0.. 1 


0. • 


0.35 








.46 












£■/ 


.35 . 
.462/ 


.35 



l/ DDT concentrate added to the firs', rinse. 
2j DDT concentrate added to the second rinse. 

Tests with Hand-Washed Woolens 

Since small woolen articles, such as sw- , socks, and gloves, 

often washed by hand, the use of DDT nonionic emulsifiable concen- 
trate for :ig such articles during the hand-washing procedure « 
also investigated. 

Procedure 

A DD I emulsifiable concent! 

rinse water (100 r . of 1 tablespoonful per pound 1. 

rhe woolens were placed In the rinj 

, md then '■ 
. ■ hi rticles w< hire, 

l he centrat( ised In I '•'» 

■ • i X- 100, and 9 ... 



A 

DDT Ln the rinse, and th n the • 

lie blai 
ichinei . 



11 



Table 6. --Deposit of DDT in woolens washed by hand 



Article 


Weight of 
woolens 


DDT concen- 
trate added 


DDT in woolens 
(by weight) 


DDT exhausted 
from bath 




Grams 


Milliliters 


Percent 


Percent 


Sweater 


121 


4 


0.50 


58 


Sweater, socks, 










and gloves 


212 


7 


.49 


49 



Tests with Colored Yarns 

To find out whether dyes influenced the amount of DDT picked up by 
wool when treated with DDT nonionic emulsifiable concentrates in the 
wash, a series of yarn treatments was made in a Laundrometer. 

Procedure 

White, pink, and blue knitting yarns were washed and treated in water 
at 100° F. for 15 minutes and rinsed twice for 1 minute in water at 85°. 
In the wash a 0.2-percent concentration of neutral soap was used. A 30- 
percent DDT nonionic emulsifiable concentrate was added with the soap 
at the rate of 1 tablespoonful per pound of wool. Two pieces of khaki 
wool blanket were included for comparison. 

Results 

As shown in table 7, none of the dyes on the treated yarns had any 
apparent effect on the amount of DDT exhausted from the bath or the 
amount deposited on the yarns. There was no indication that the dyes 
were affected by the DDT treatment. 

Table 7. --DDT deposit in colored yarns treated in a Laundrometer 



Color and type 


Weight 


DDT concen- 


DDT in yarn 


DDT exhausted 


of yarn 


of yarn 


trate added 


(by weight) 


from bath 




Grams 


Milliliters 


Percent 


Percent 


White: 










4-ply 


7.95 


0.26 


0.37 


37.6 


3-ply 


7.00 


.25 


.20 


18.7 




5.22 


.17 


.20 


20.4 


Pink: 










4-ply 


7.27 


.24 


.39 


39.3 




8.43 


.28 


.34 


34.2 


3-ply 


8.33 


.27 


.37 


38.0 




7.21 


.24 


.34 


34.0 


Blue, 3-ply 


7.10 


.23 


.48 


49.4 




8.94 


.30 


.21 


20.9 


Khaki blanket 


12.37 


.41 


.20 


20.1 




12.22 


.40 


.23 


23.4 



- 12 



♦ion o -ns 

■ '. 

.1 test with blar -ns tr- 

nine the degree ol 

1 v. • nt and conducted . ordance with tl .!A 

onsis- osing samples of 

• aals to 10 larvae of the bla .e ( Attag- 

(Oliv.)) in open petri dishes for 28 days. The exposu 

;ng a constant temperature of 80° 1 2° F. anc 
humidity of 60 1 5 percent. Insect mortal; , sual damage, and frass 
weight lght loss of wool 9 ecorded at the end of the exposu 

As shown in table 8, very light surface damage was obtained 
DDT deposit level of 0.06 percent by weight of the wool, but above that 
level no damage occurred. 

Table 8. --Results of biological tests with black carpet beetle lar. 
exposed to blankets and yarns containing various levels of DDT 
deposit 



DDT in material 


Visual 


Frass weight 




ss of 


(by weight) 


damage 


per larva 




ol 


Percent 


Bla 


M 
nkets 


as 


M 


illi j 


0.06 


Ve : ;■ light 




0.3 




- 




None 




. 00 




- 








. 




- 


.08 


' 




.75 




- 


.1 1 


Noi 




. 




- 








3.81 




- 















I 

None 
None 

i 












- 13 - 



Sweater, Socks, and Gloves 

Additional biological tests were conducted with a woolen sweater, 
a pair of socks, and a pair of gloves. 

Half a sweater, one sock, and one glove were treated with DDT 
emulsion and the remainder was left untreated. The treated articles 
contained 0.49 percent of DDT by weight of the wool. The treated and 
untreated articles were placed individually in cardboard boxes 3 by 10 
by 12 inches with 100 larvae of the black carpet beetle and 50 of the 
webbing clothes moth ( Tineola bisselliella (Hum.)). The boxes were 
sealed with masking tape to prevent escape of the insects. They were 
kept for 5 months in a room at a constant temperature of 80°t2°F. and 
relative humidity of 60 t 5 percent. They were inspected monthly and 
after 1 and 3 months insects were added at the same rate as in the initial 
infestation. 

After a 1 -month exposure the untreated articles were moderately 
damaged and the insects were alive and feeding. A large number of 
clothes moth adults were present in the boxes. There was no damage 
on any of the treated articles, and all the insects were either dead or 
inactive. 

After 2 months further damage had been done to the untreated 
articles and a healthy insect population was being maintained. The 
treated articles still showed no damage, and the condition of the insects 
was similar to that found after the first inspection. 

After 5 months the untreated articles were very badly damaged, 
whereas no damage was visible on the treated woolens (fig. 1). The 
insects exposed to the untreated articles were alive and active, and 
the number of webbing clothes moths had increased considerably. All 
the insects exposed to the treated woolens were dead or inactive. 

Long-term biological tests were also conducted to determine the 
duration of effectiveness of low DDT concentrations in protecting 
woolens against insect damage. Woolen material was exposed con- 
tinuously for 44 months in a small chamber containing an active in- 
festation of clothes moths, black carpet beetles, and furniture carpet 
beetles (Anthrenus flavipes Lee). The residue on the treated cloth 
ranged from 0.10 to 0.17 percent DDT by weight of the fabric, with an 
average of 0.14 percent. Periodic inspections revealed that the un- 
treated material had been badly damaged, but the treated cloth still 
has no visible damage. 

Summary 

During the course of investigations with DDT for protecting woolens 
against fabric insects, it was noted that, after woolen cloth was treated 
in a dilute nonionic DDT emulsion, the DDT deposit was considerably 
greater than the theoretical deposit calculated from the amount of 



14 - 



emuls y the cloth. Labr sts ur -en to le. 

mo: ! the one 

suits also showed 1 \trol the amour.- )[J'l 

I in the < I using di. 

Subsequent : shable woolen> 

• • cial laundry machines, • '>'P e autc J nonautom. 

shing mai bines, and durin. ng sv.' -.elusions 

of soap-, 
water softeners had no noticeable effect on the rate ol 
pickup by the wool. N 1 rinsing imm' . eatment in the 

hing machines did not remove a: ount of DDT . 

dif f • in the deposit resul' :ns of 

i. Th- unt ol Dl the treated woolens ranged 

'o 54 percent of that pr( -mulsion, depending on 

d, thi , and the con< . of 

I I in the bath. 
In bio] sts a residue as 1 . 18 peroent of DDT 

the fabric prevented dam; ; ad 

sidues of 0.1 percent or above prevented damage b pet beetb 

and clothes moth.-.. 1 pickup obtained in tl me 

tablespoonful (14.8 ml.) of 25- to 30 ent DO 1 emulsifiable 

und of wool added to the wash o: 
laundry process gave a DDT deposit of more than * 

Li <id 

(1) Goodall, F, L. a Gorton, 1. K., and Summersgill, J. 

DI) I tions. :id 

. 

H ... s. A., Schechter, M S nd 

I «, Chemici I DDT. I . S. 1 . ; . .nd 

r ntQuar. El 211. 6 pp. 

(3) Jones, H. A., McAllister, L.C.j . C, 

15, DDi impri 

Joui . Econ. Ent. 

( 4) " , R. W, 

. Mothproofing, p. . I • I H , Ltd., L 



- 15 - 




Figure 1. --Treated (left) and untreated (right) portions of a sweater 
after a 5 -month exposure to fabric insects. 



ii i mi in hi 

3 1262 09239 6489